Worked on the denoland/typescript-go repository to enhance the reliability of BigInt literal parsing by expanding test coverage for binary, octal, and hexadecimal formats, including support for underscores and uppercase prefixes. Developed a dedicated test suite in Go, focusing on validating edge cases to ensure accurate parsing behavior and safer interoperability between TypeScript and Go implementations. Emphasized test-driven development practices and improved CI readiness by delivering a single, targeted feature commit. This work strengthened code quality and maintainability for numeric literal parsing, reducing potential runtime errors in real-world TypeScript codebases that rely on BigInt literals. Skills used included Go programming and unit testing.